Today's dishwashers are expected to perform high quality wash of dishware, and environmental concerns require an efficient use of energy during operation. Also, it is an advantage if washed items are dry after a washing phase. In the last phase of a wash cycle, water is sprayed in to the dishwasher in order to rinse the washed items. After stopping, the remaining water will form drops and pools on the washed items and at the racks. The drops are held on surfaces due to the surface tension in the droplets and are hanging from washed items, racks and places where the washed items and racks meet each other. The water will slowly evaporate and the size of the drops will gradually be reduced. In the last phase of a wash cycle, warm water may be sprayed in to the dishwasher in order to heat the washed items. In addition, modern dishwashers may use heat during a drying phase to dry the washed items, for example by having heaters within the dishwasher and/or by blowing warm air inside the dishwasher. One problem is that the use of heat during a drying phase requires a large amount of energy. Further, such drying process using heat is time consuming.
Attempts have been made to reduce energy consumption during a drying phase of a dishwasher. The document FR2879429 A1 relates to a dishwasher comprising electromechanical vibration generators connected to racks of the dishwasher. The vibration generators generate vibrations that are transmitted to the racks and to the dishware accommodated at the racks in order to remove water droplets from the racks and the dishware. The dishwasher in the document is associated with some problems. One problem is that the vibrations transmitted to the racks will also be transmitted to dishware accommodated in the racks which will cause the dishware to rattle. Obviously, this will generate noise. Further, not all washing liquid will be removed from the racks and the dishware using vibration generators described in the document.